Hydraulic Bulge Test of Al and Copper Tubes

Abstract

This work aims to find forming limit diagram and mechanical propertiesexperimentally to measure formability by hydraulic bulge test and tensile test, anddetermination the values of the bursting pressure and final thickness in the finalstage at bursting experimentally and numerically by using program (ANSYS 11) toperform numerical simulation for copper and aluminum alloy (6060) tubes beforeand after heat treatment by hydraulic bulge test.In this work, used two types of tubes with dimensions for copper of(L0=150mm, d0 = 41.275mm, t0 = 1.06mm) and for aluminum alloy (6060) are(L0=150mm, d0 = 60mm, t0 = 2 mm). Applied heat treatment (annealing) of copperand aluminum tubes at temperature (450°C, 400°C).the holding time in the furnacewas 1 hour and then cooled in the furnace. Has been printed square grid by screenmethod with dimensions (5x5 mm) for copper and aluminum tubes before and afterheat treatment and with dimensions (2.5x2.5 mm) for tensile samples of copper andaluminum before and after heat treatment. Strain Measurement accomplished byusing image processing technology using MATLAB by measuring the dimensionsof the grid printed before and after the deformation and then measure the true strainon tensile samples and tubes used in the tensile test and hydraulic bulge test beforeand after heat treatment.The results show that, the values of the bursting pressure and final thickness inthe final stage at bursting for copper tube before and after treatment is (29MPa,27MPa)،( 0.892mm, 0.621 mm) and for aluminum tube before and after treatmentis (19MPa, 16MPa),( 1.789mm, 1.4872 mm). Increasing formability anddecreasing bursting pressure of tubes after heat treatment of increasing the strainhardening exponent (n) of tubes.